JP5496264B2 - Vacuum insulation panel - Google Patents

Description

  The present invention relates to a vacuum heat insulation panel with improved gas barrier properties.

In general, when vacuum insulation is placed inside a refrigerator door or wall, inside a transport vehicle wall, etc., the vacuum should not be broken by external factors and should be maintained for a long time. In order to maintain it, the core material is put in an envelope made of a skin material laminated with a plurality of layers, and the inside is evacuated and then sealed by heating and fusing the entrance.

As the skin material, the innermost layer is a heat-sealing layer, and several barrier layers and protective layers made of a metal vapor deposition film or the like are stacked on the outer side of the heat-sealing layer. For example, Patent Document 1 discloses a skin material in which a barrier layer, an internal protective layer, and an external protective layer are sequentially laminated on the outer side of a heat-sealing layer.

Patent Document 2 discloses that a film is further provided on the outside of the vacuum heat insulating panel, and Patent Document 3 discloses that a second heat-sealing is further performed outside after the sealing portion is heat-sealed. It is disclosed.

JP 2012-026512 A JP-A-11-2013377 Japanese Patent Laid-Open No. 11-210983

  FIG. 3 is an enlarged cross-sectional view of a sealing portion of a conventional vacuum heat insulating panel, and an end surface of the sealing portion is a layer constituting the outer skin material (a heat sealing layer 101, a barrier layer 102, a protective layer 103, and an adhesive layer 104). ) Is exposed for that thickness. The problem is that because the heat-sealable layer is exposed by the thickness, gas molecules penetrate through the heat-sealable layer, and the heat-sealable layer and the barrier layer are bonded together. It is joined through an agent layer, and gas molecules also enter through this adhesive layer.

  For example, since the diameter of the water molecule is about 3 mm, it easily enters the vacuum space through the heat sealing layer or the adhesive layer between the heat sealing layer and the barrier layer, and the vacuum is broken.

In Patent Document 1, a thin portion is formed in the sealing portion to reduce the thickness of the heat-sealing layer to prevent gas intrusion, but this is not sufficient, and a sufficient vacuum state for a long period (10 years or more) In order to maintain this, it is necessary to put a large amount of adsorbent in the interior, which causes an increase in cost.
Similarly, the structures disclosed in Patent Documents 2 and 3 cannot effectively prevent the invasion of gas molecules.

  In order to solve the above problems, the vacuum heat insulation panel according to the present invention has a multi-layer structure in which the outer cover material that covers the outside of the core material in an airtight manner has the innermost layer as a heat fusion layer. A metal or silica vapor deposition film was formed on at least one of the inner and outer surfaces.

  When a vapor deposition film is provided on the outer surface of the heat-sealing layer, gas can be prevented from entering from the adhesive layer between the heat-sealing layer and the barrier layer. When the deposited film is provided, it is possible to prevent gas from entering through not only the adhesive layer but also the heat-sealing layer. Therefore, it is more preferable to provide a vapor deposition film on the inner surface of the heat-fusible layer.

The thickness of the deposited film is preferably 1 to 500 nm. If it is less than 1 nm, the gas barrier effect is insufficient, and if it is thicker than 500 nm, the fusion between the heat-sealing layers may be hindered, so the above range is preferable.

  According to the present invention, gas can be prevented from entering the vacuum heat insulating panel from the sealing portion, the vacuum state in the panel can be maintained for a long time, and the heat insulating effect can be exhibited for a long time.

Sectional drawing of the sealing part of the vacuum heat insulation panel which concerns on this invention 1 is an enlarged cross-sectional view of the main part of FIG. Sectional view of the sealing part of a conventional vacuum insulation panel

Examples of the present invention will be described below. In the vacuum heat insulation panel according to the present invention, the core material 1 is airtightly covered with the outer skin material 2.
The core material 1 is made of a glass wool molded body, and this glass wool molded body is a three-dimensional framework structure in which the intersections of fibers are joined with an inorganic binder such as water glass.

The outer skin material 2 has an airtight bag shape by covering the upper and lower surfaces of the core material 1 and thermally welding the periphery. The outer skin material 2 is a multilayer in which a heat sealing layer 3, an adhesive layer 4, a barrier layer 5, an adhesive layer 6, a first protective layer 7, an adhesive layer 8 and a second protective layer 9 are laminated in that order from the inside. It has a structure.

The heat fusion layer 3 is made of a thermoplastic resin such as low-density polyethylene, and a vapor deposition film 10 made of metal or silica and having excellent gas barrier properties is formed on the inner and outer surfaces thereof. In the illustrated example, the vapor deposition film 10 is formed on both surfaces of the heat-sealing layer 3, but it may be formed only on one surface.

In the fusion part, the vapor deposition films 10 formed on the inner surface of the heat fusion layer 3 overlap each other. However, since the thickness of the vapor deposition film 10 is 1 to 500 nm, the fusion layers 3 are fused to each other. There is no problem.

The thickness of the heat sealing | fusion layer 3 shall be 10-100 micrometers, for example. If it is too thin, the adhesive strength is inferior, and if it is too thick, the sealing time becomes longer and the efficiency is lowered, which is disadvantageous from the viewpoint of economy and workability.

As the barrier layer 5, an aluminum foil or an aluminum vapor deposition film is used, and as the first protective layer 7 and the second protective layer 9, a nylon film or a polyethylene terephthalate film is used.

  The vacuum heat insulation panel according to the present invention can be used in places where heat insulation is required, such as the inside of doors and panels of refrigerators and freezers, the inside of the body of a transport vehicle, the inside of a building wall, and the inside of an aircraft body.

  DESCRIPTION OF SYMBOLS 1 ... Core material, 2 ... Skin material, 3 ... Heat-fusion layer, 4 ... Adhesive layer, 5 ... Barrier layer, 6 ... Adhesive layer, 7 ... 1st protective layer, 8 ... Adhesive layer, 9 ... Second protective layer, 10 ... deposited film.

Claims (3)

In the vacuum heat insulating panel that covers the outside of the core material with an outer skin material and maintains the vacuum state inside, the outer skin material has a multilayer structure in which the innermost layer is a heat fusion layer, and the heat fusion layer A vacuum heat insulating panel characterized in that a metal or silica vapor deposition film is formed on at least the inner surface of the vacuum heat insulating panel.   The vacuum heat insulation panel according to claim 1, wherein the deposited film has a thickness of 1 to 500 nm. The vacuum heat insulation panel according to claim 1 or 2, wherein the deposited film is formed on an inner side surface and an outer side surface of the heat fusion layer.

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